The Biomarker Core will be primarily located in the Translational Research Laboratory (TRL), the same building which houses the Center for Sleep and Respiratory Neurobiology. The formation of the Biomarker Core will take advantage of existing facilities and the sophisticated equipment already available within the Translational Research Laboratory. The Biomarker Core will act as a central facility to collect, process and analyze the large number of incoming blood and urine samples generated by the clinical Projects 02 and 03 as well as rat tissue samples and isolated human monocytes derived from Projects 01 and 03. Importantly, the Biomarker Core will ensure quality control of all samples collected by the proposed projects. The objectives of the Biomarker Core are to: 1) standardize blood and urine collection between sites, 2) ensure proper handling and storage of samples, 3) code, record and monitor incoming samples 4) ensure quality control of assays and 5) provide a centralized facility for assays that are not available at other facilities within the institute. The Biomarker Core will be under the leadership of Dr. Karen Teff with Dr. Miroslaw Mackiewicz as Co-Core Leader and support staff consisting of a senior research technician and minimal effort from an additional technician in Dr. Teff's laboratory. Biomarkers will fall into the following categories: markers of oxidation and protective anti-oxidants, pro-inflammatory and anti-inflammatory markers, adhesion molecules, indices of insulin resistance and indices of sympathetic nervous system activity. The Biomarker Core will conduct three types of assays: 1) high-pressure liquid chromatography (HPLC) for measurement of plasma and urinary norepinephrine and metabolites such as normetanephrine as well as melatonin, a specific sleep-related biomarker, 2) spectrophotometric methods for the analysis of free fatty acids and triglycerides and 3) Reverse Transcription - Polymerase Chain Reaction (RT-PCR) on rat tongue tissue and isolated human monocytes. To avoid duplication of resources, we will take advantages of other cores at Penn. The Clinical and Translational Research Center Laboratory routinely conducts Enzyme Linked Immunosorbent Assay (ELISA) for the measurement of the inflammatory cytokines (IL-6, TNF-a), the anti-inflammatory cytokine (IL-10) and adhesion molecules (ICAM-1). In addition, markers of insulin resistance and sensitivity requiring radioimmunoassays (insulin, leptin, adiponectin) will be measured by the Penn Diabetes Research Center Radioimmunoassay Core. Urinary isoprostanes will be measured in the laboratory of Dr. Ian Blair, Professor of Chemistry and a renowned expert in markers of oxidative stress. Plasma glucose will be analyzed in the laboratory of Dr. Teff. A centralized facility will ensure quality control and cost effectiveness and will support future projects by establishing a bank of samples that will be available for future investigation.